This invention relates generally to hopper discharge apparatus and, more particularly, to a hopper discharge apparatus for delivering the contents of the hopper from a side port toward alternative delivery points directly below the hopper and alongside it. In one particularly important embodiment, the invention is concerned with a discharge apparatus designed for attachment to a side delivery gravity flow grain box for unloading the grain alternatively onto a conveyor alongside the box or into a pit directly below it.
Hopper structures of myriad types are known for storing and dispensing granular materials such as grain, coal, powdered chemicals, etc. One common type of hopper structure which is particularly well suited for application of the present invention comprises an open-top vessel having an inclined floor and at least one sidewall with a port at the point where the floor joins the sidewall. Unloading this hopper is accomplished simply by opening the port, thereby permitting the material within the hopper to discharge through the port under the force of gravity, following the incline of the hopper floor. Usually a chute is affixed to the port to direct the material to a point alongside the hopper.
Modern mechanized farming operations typically utilize large hoppers, known as "grain boxes", to receive and store grain during harvest season. In one particularly important farming application, these grain boxes are mounted on a running gear or carriage and hauled alongside a combine as it moves through a field harvesting grain. As the grain is harvested by the combine it is propelled into the grain boxes which eventually are hauled from the fields to a grain elevator or other storage facility for unloading.
The two most popular types of carriage-mounted grain boxes in general usage are the side delivery box and the center delivery box. The center delivery box has opposite slanted floor portions meeting in a center port which releases the grain from directly below the box in a manner very similar to the way in which a typical railroad coal car is unloaded. The side delivery box utilizes the slanted floor and side port structure described earlier as being particularly well suited to the application of the present invention. These two types of grain boxes have come into popular usage because they work well with the typical unloading systems found at grain elevators: (1) pit dump (center delivery boxes) and, (2) side conveyor (side delivery boxes).
Unfortunately, a farmer who invests in either center delivery or side delivery boxes compatible with the particular unloading facilities of his grain elevator may find for a variety of reasons that he must unload his grain boxes at another facility which has the opposite type of unloading arrangement. This presents a serious dilema to the farmer, since there is, at present, no inexpensive and efficient manner for adapting the center delivery box for side conveyor delivery or the side delivery box for pit dump delivery. Furthermore, economic considerations as well as space limitations prevent most farmers from maintaining fleets of grain boxes of both designs. As explained further herein, the present invention offers the farmer one approach to meeting his dual delivery needs by relying solely upon side delivery boxes.
One solution which has been proposed for this delivery problem is shown in FIG. 1. The grain box of FIG. 1 includes a hopper 10 mounted on a running gear 12 with runner gear tires 14 and supporting truss 16. Hopper 10 includes a side port 18 opened and closed by side control wheel 20 and a bottom port 22 opened and closed by bottom control wheel 24. An open side delivery chute 26 is attached to the hopper just below side port 18. An open center delivery chute 28 is also attached to the hopper, just below bottom port 22.
The dual delivery grain box of FIG. 1 is shown containing a load of grain 30 being unloaded into a pit dump (not shown) below the running gear. In this mode of operation, side port 18 is closed and bottom port 22 is open, thereby permitting the grain to exit the hopper onto chute 28.
The dual delivery arrangement of FIG. 1 has a number of serious drawbacks. This arrangement requires both side and bottom ports which adds to the expense of the hopper. Also, operation of the bottom door is extremely inconvenient, since it lies below the hopper. Finally, and perhaps most importantly, this structure cannot be retrofitted to present single delivery boxes, and thus fails to solve the problems of the many farmers who find themselves with a grain box of one delivery type and a grain elevator requiring the opposite delivery.
In addition to the approach of the FIG. 1 dual delivery grain box, less sophisticated approaches to solving the delivery compatibility problem have been proposed. For example, farmers having side delivery boxes but center delivery requirements have simply swung the side chute up out of the way, and placed a flat board below the side port, angled to the pit dump. This approach, however, is very inefficient since grain bounces and slides off the board and is spilled onto the ground. Another very similar approach which has been suggested is to attach a deflector to the bottom of the side chute in such a way that, when the chute is swung up out of the way the deflector is moved into position below the port and pointed towards the center of the grain box. This has the same drawbacks as the simple flat board arrangement since grain is lost into the air or directed to locations short of the pit. Also, since the deflector must be very small to prevent interference between the deflector and the running gear when the side chute is in its side delivery position, the deflector is probably less efficient than the flat board arrangement.